[PATCH v1 0/2] perf tool: improve error handling in perf_flag_probe()

[Yann Droneaud <ydroneaud@opteya.com>]

Hi,

Following the EBUSY errors reported by Jiri Olsa [1], I've tryed to
improve a bit the way perf_flag_probe() handle errors.

In case EBUSY is returned by perf_event_open(), testing the function
again without PERF_FLAG_FD_CLOEXEC is meaningless: EBUSY is not
related to close-on-exec flag, so there's nothing to confirm.

For other errors, not yet explicitly handled by perf_flag_probe(),
it's pointless to report a second error message for the same error
code: the second check should not print an error if the error is
the same as the one returned for the first check.

Changes from v0 [2]:
 - rebased on top of commit 48536c9195ae ("perf tools: Fix probing for PERF_FLAG_FD_CLOEXEC flag");
 - update a bit commit message;
 - the previous patchset was acked by Jiri[3], but I haven't
   reported Acked-by: in this updated patchset.

[1] http://lkml.kernel.org/r/1406908014-8312-1-git-send-email-jolsa@kernel.org
[2] http://lkml.kernel.org/r/cover.1410595700.git.ydroneaud@opteya.com
[3] http://lkml.kernel.org/r/20140920121438.GB15481@krava.brq.redhat.com

Yann Droneaud (2):
  perf tools: shortcut PERF_FLAG_FD_CLOEXEC probing in case of EBUSY
    error
  perf tools: report PERF_FLAG_FD_CLOEXEC probing error once

 tools/perf/util/cloexec.c | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

Regards.

--
Yann Droneaud
OPTEYA